The Nature and Origin of Supraspecific Taxa

Abstract

The original plan for this paper was to attempt a general theoretical discussion of the definition, nature, and evolutionary significance of taxonomic categories above the species. It soon became evident, however, that such a broad approach was too ambitious and would cover far too much ground for a single contribution to a symposium by so many authors. I have therefore decided to present only a few explicit phylogenetic examples at higher categorical levels, especially from subfamilies to classes. Many theoretical points are evident in these examples but are not separately discussed. Definitions of categories, considerations of abstract phylogenetic patterns, the historical development of thought about higher categories, and numerous related subjects are also deferred to some other occasion. The examples are drawn from materials relatively familiar to me, mostly the fossil and living mammals, but they have fairly obvious implications for almost any organisms.